Mississippi's two U.S. senators included $700 million in an emergency war spending bill to relocate a Gulf Coast rail line that has already been rebuilt after Hurricane Katrina at a cost of at least $250 million.

Republican Sens. Trent Lott and Thad Cochran, who have the backing of their state's economic development agencies and tourism industry, say the CSX freight line must be moved to save it from the next hurricane and to protect Mississippi's growing coastal population from rail accidents. But critics of the measure call it a gift to coastal developers and the casino industry that would be paid for with money carved out of tight Katrina relief funds and piggybacked onto funding for the wars in Iraq and Afghanistan.

"It is ludicrous for the Senate to spend $700 million to destroy and relocate a rail line that is in perfect working order, particularly when it recently underwent a $250 million repair," said Sen. Tom Coburn (R-Okla.), who is planning to challenge the funding when the $106.5 billion war spending bill reaches the Senate floor. "American taxpayers are generous and are happy to restore damaged property, but it is wrong for senators to turn this tragedy into a giveaway for economic developers."

Securing money for pet home-state projects is nothing new for Lott, a famous benefactor of the Mississippi coastline, or for Cochran, chairman of the Senate Appropriations Committee. But the fight over the rail funding will come at a sensitive time, when both houses of Congress have promised to rein in such "earmarks" as part of a larger effort to overhaul ethics rules, and when a stubborn budget deficit has made spending of all kinds a sensitive political issue.

At $106.5 billion, the Senate Appropriation Committee's version of the emergency spending bill is already more than $14 billion larger than the version the House passed in March. The Senate bill will probably reach the floor next week.

A $223 million "Bridge to Nowhere" -- linking Alaska's tiny Ketchikan to its airport on Gravina Island -- in last year's highway bill turned into a political firestorm that some Republicans still fear has dampened the spirits of conservative voters. Budget watchdogs are already tagging the Lott-Cochran provision the "railroad to nowhere."

"We have real needs that we have to meet for rebuilding in the Gulf Coast, and with our tight budgets, this is almost a zero-sum game," said Steve Ellis, vice president of Taxpayers for Common Sense. "And now we're taking about moving a railroad that's been rebuilt already? That doesn't make sense."

Writing yesterday in the Biloxi Sun Herald, Lott called the "railroad to nowhere" tag outrageous, daring his critics "to see this situation for themselves before passing judgment on the expendability of Mississippi lives."

Lott cited his father's death "on a narrow, two-lane road" as a reason for his safety concerns.

But even appropriations aides who are sympathetic to the earmark say the issue is more complicated than Lott's case for safety. There are inherent safety issues when rail lines run through populated areas, but those issues exist nationwide. Mississippi's rail-accident rate from 2001 to 2005 reached a 30-year low.

Much of the rail line along the Gulf Coast would remain in hurricane danger, and the proposed rerouting would affect only a small part.

The real impetus appears to be economic. For more than half a dozen years, Mississippi officials, development planners and tourism authorities have dreamed of the complex restructuring of Mississippi's coastal transportation system that Lott and Cochran now want to set in motion. Under the plan, the CSX line -- which runs a few blocks off the coast line -- would be scrapped. CSX would move its freight traffic to existing tracks to the north owned by rival Norfolk Southern.

Then U.S. 90, a wide federal highway that hugs Mississippi's beaches, would be rebuilt along the CSX rail bed. The route of the federal thoroughfare would be turned into a smaller, manicured "beach boulevard" through cities such as Biloxi, where visitors could "spend more time strolling among the casinos and taking in the views," as the Governor's Commission on Recovery, Rebuilding and Renewal put it.

"There's nothing wrong with this if Mississippi wants to do it. Mississippi wanted to do it before the hurricane," Coburn said. "But why is it a federal responsibility? Why should our grandchildren pay for it?"

The $700 million in the emergency spending bill is just short of the price CSX set for selling its right of way, buying into the Norfolk Southern line, making capacity improvements on the main line and bolstering a short line railway to bypassed areas. The high price was inevitable, Appropriations Committee aides said. CSX just spent as much as $300 million in insurance payouts and its own money to rebuild the track that Lott and Cochran now want to destroy.

And the cost would increase considerably if, as expected, Lott looks to annual appropriations bills to rebuild U.S. 90.

Susan Irby, Lott's communications director, said safety is the senator's biggest concern. But she added: "Senator Lott makes no apologies for trying to develop one of the poorest states in the country."